Senior Staff / Staff Backend Engineer (Security Infrastructure)

Coupang

DESCRIPTION We exist to wow our customers. We know we’re doing the right thing when we hear our customers say, “How did we ever live without Coupang?” Born out of an obsession to make shopping, eating, and living easier than ever, we’re collectively disrupting the multi-billion-dollar e-commerce industry from the ground up. We are one of the fastest-growing e-commerce companies that established an unparalleled reputation for being a dominant and reliable force in South Korean commerce. We are proud to have the best of both worlds — a startup culture with the resources of a large global public company. This fuels us to continue our growth and launch new services at the speed we have been since our inception. We are all entrepreneurs surrounded by opportunities to drive new initiatives and innovations. At our core, we are bold and ambitious people that like to get our hands dirty and make a hands-on impact. At Coupang, you will see yourself, your colleagues, your team, and the company grow every day. Our mission to build the future of commerce is real. We push the boundaries of what’s possible to solve problems and break traditional tradeoffs. Join Coupang now to create an epic experience in this always-on, high-tech, and hyper-connected world. Role Overview As part of our Application Infrastructure org, this is a greenfield team that will impact complex Coupang workflow systems. We need to create a set of systems that will allow rapid workflow development for hundreds of domain teams, allowing critical infrastructure like rocket delivery service. It is a highly visible system with hundreds of millions of dollars of revenue flowing through the systems. It is a chance to design from scratch, and create a reliable workflow service at scale. We are looking for a Senior/Staff Engineer to lead the architectural design and implementation of our next-generation durable execution platform. This team is tasked with building a highly scalable, fault-tolerant system from scratch that enables developers to write long-running, reliable workflows as code. At Coupang, we Aim High and Find a Way to solve impossible problems. You will be responsible for building a system that doesn't just meet industry standards but sets them, ensuring 5-6 nines availability while leveraging AI to automate complex system behaviors and self-healing capabilities What You Will Do * Define Extreme Availability: Design for "5-6 nines" (99.9999% availability). You will Dive Deep into the tail latencies and edge cases of distributed state management to ensure our platform is always on for our customers. * AI-Driven Automation: Integrate AI/ML models to automate system functionality, including predictive scaling, automated bottleneck detection, and intelligent error recovery, ensuring we Wow the Customer through seamless platform performance and availability. * Solve Hard Problems: Address challenges related to distributed locking, timers, and deterministic execution. You must Be Data-Driven to validate architectural decisions against massive traffic patterns. * Stakeholder management - Work cross functionally with our product teams to provide infrastructure which serves the company’s business needs Basic Qualifications * Bachelor's degree in computer science, Electrical Engineering, Math, or a closely related field * 8 years+ of experience in backend software development * Proficiency in Java and the Spring Framework * Experience working in cloud environments, particularly AWS * Demonstrated experience in building and maintaining highly available, distributed systems   Preferred Qualifications * Extensive Experience: 12+ years of professional software development experience, specifically building backend infrastructure that supports global-scale traffic. * High Availability Mastery: Proven track record of managing and maintaining systems with 5-6 nines of availability. You understand that "good enough" isn't enough; we Focus on the Customer and the Experience by ensuring zero downtime. * Distributed Systems Expert: Deep expertise in designing and deploying mission-critical systems (e.g., databases, messaging queues, or orchestration engines) from the ground up. * Technical Mastery: Expert-level proficiency in Java, Python with deep understanding of concurrency and memory management. * AI Integration: Experience or a strong architectural vision for using AI/ML to automate system-level functionality and operational tasks. * Specialized Knowledge: Deep familiarity with the Temporal or Cadence programming models and their underlying architecture. Experience in Kubernetes and containerization. * Stateful Database Experience: Experience with Cassandra and TiDB preferred * Observability Expert: Expertise in building highly observable systems using distributed tracing and advanced telemetry to proactively identify issues.   Recruitment Process  Application Review - Phone Interview - Onsite (or Virtual Onsite) Interview – Offer  The exact nature of the recruitment process may vary according to the specific job and may be changed due to scheduling or other circumstances.  Interview schedules and the results will be informed to the applicant via the e-mail address submitted at the application stage.     Details to Consider   * This role is open to Singapore Citizens and Permanent Residents only  * This job posting may be closed prior to the stated end date for application if all openings are filled.  * Coupang has the right to rescind an offer of employment if a candidate is found to have submitted false information as part of the application process.  * Those eligible for employment protection (recipients of veteran’s benefits, the disabled, etc.) may receive preferential treatment for employment in accordance with applicable laws.  * Job titles and responsibilities may be subject to change depending on the candidate’s overall experience, etc. This will be communicated to the candidate at the appropriate time before the offer.  * Hiring may be restricted in case the legal qualifications required for hiring and work performance is not met.    Privacy Notice    Your personal information will be collected and managed by Coupang as stated in the Application Privacy Notice located below.      https://privacy.coupang.com/en/land/jobs/

Coupang

Company Introduction  We exist to wow our customers. We know we’re doing the right thing when we hear our customers say, “How did I ever live without Coupang?” Born out of an obsession to make shopping, eating, and living easier than ever, we are collectively disrupting the multi-billion-dollar commerce industry from the ground up and establishing an unparalleled reputation for being leading and reliable force in South Korean commerce.   We are proud to have the best of both worlds — a startup culture with the resources of a large global public company. This fuels us to continue our growth and launch new services at the speed we have been since our inception. We are all entrepreneurs surrounded by opportunities to drive new initiatives and innovations. At our core, we are bold and ambitious people that like to get our hands dirty and make a hands-on impact. At Coupang, you will see yourself, your colleagues, your team, and the company grow every day.     Our mission to build the future of commerce is real. We push the boundaries of what’s possible to solve problems and break traditional tradeoffs. Join Coupang now to create an epic experience in this always-on, high-tech, and hyper-connected world.    Role Overview  At Coupang, we invest in providing the best product experience for our customers. The AI and Knowledge Engineering team’s mission is to provide the best possible technical solution to achieve the optimal experience for our customers. We innovate and advance the space of Knowledge Graphs, AI agents, LLMs, AIGC, ML, NLP, CV and multi-modal models. We are looking for engineers who want to work on cutting edge technology, that is the intersection of Semantic knowledge bases, AI agents, NLP, LLM, AIGC, ML and software engineering. Come join us to help create a world class team advancing the AI/NLP/AIGC/ML/LLM/RL/Knowledge Graph technologies.   What You Will Do  * Work on GenAI, AI agents' systems to solve complex eCommerce scenarios. * Develop large language and vision understanding/generation models for predictive and compound AI Models * Train foundational models that can help with building learning systems. * Define process and experiments for an E2E foundation model. * Build E2E AI pipelines for storing/servicing foundational models. * Mentor and guide team members on frameworks, methodologies related to data lakes, data normalization, dimension reduction, visualization, statistical models. * Ensure Model training is security, compliance aware. * Collaborate with cross-team members to understand the requirements ensuring the foundational models; knowledge captured aligns with the company’s overall AI strategy.    Basic Qualifications * 5+ years of demonstrated data science, experience in building large scale foundational models for eCommerce scenarios. * Expertise in large language model post-training and deployment. * Deep understanding of AI/LLM/AIGC/ML architecture. * Strong statistical/mathematical background in defining metrics, learning functions, and result analysis. * Significant experience in SQL, Python, PySpark, Scala and R * Proficiency in PyTorch/TensorFlow, Spark, BigQuery * Proficiency in AI coding Cursor/Windsurf/Claude Code/Codex. * Experience creating complex data visualization tools, frameworks, and techniques. * Experience in dimension reduction in big data. * Proficient in cloud analytical stacks [ Lakes, warehouse, ETL pipelines] * Experience with inference platforms in AWS, Azure, and other open-source platforms. * Result-oriented, with a bias towards customer obsession, flexibility, and impact. * Strong written and verbal communication and teamwork skills * Passion for Large language models, NLP, and Machine Learning at scale * Education: B.S, M.S in Computer science or Mathematics, or related field   Recruitment Process  * Application Review -> Phone Interview -> Onsite (or Virtual Onsite) Interview –> Offer  * The exact nature of the recruitment process may vary according to the specific job and may be changed due to scheduling or other circumstances.  * Interview schedules and the results will be informed to the applicant via the e-mail address submitted at the application stage.     Details to Consider   * This job posting may be closed prior to the stated end date for application if all openings are filled.  * Coupang has the right to rescind an offer of employment if a candidate is found to have submitted false information as part of the application process.  * Those eligible for employment protection (recipients of veteran’s benefits, the disabled, etc.) may receive preferential treatment for employment in accordance with applicable laws.  * Job titles and responsibilities may be subject to change depending on the candidate’s overall experience, etc. This will be communicated to the candidate at the appropriate time before the offer.  * Hiring may be restricted in case the legal qualifications required for hiring and work performance is not met.    Privacy Notice   Your personal information will be collected and managed by Coupang as stated in the Application Privacy Notice located below.   https://privacy.coupang.com/en/land/jobs/

Coupang

Company Introduction  We exist to wow our customers. We know we’re doing the right thing when we hear our customers say, “How did I ever live without Coupang?” Born out of an obsession to make shopping, eating, and living easier than ever, we are collectively disrupting the multi-billion-dollar commerce industry from the ground up and establishing an unparalleled reputation for being leading and reliable force in South Korean commerce.   We are proud to have the best of both worlds — a startup culture with the resources of a large global public company. This fuels us to continue our growth and launch new services at the speed we have been since our inception. We are all entrepreneurs surrounded by opportunities to drive new initiatives and innovations. At our core, we are bold and ambitious people that like to get our hands dirty and make a hands-on impact. At Coupang, you will see yourself, your colleagues, your team, and the company grow every day.     Our mission to build the future of commerce is real. We push the boundaries of what’s possible to solve problems and break traditional tradeoffs. Join Coupang now to create an epic experience in this always-on, high-tech, and hyper-connected world.    Role Overview  The Identity, Access and Protection Infrastructure team builds the platform that secures all our services and customer interactions. We accelerate Coupang’s business through our industry-leading security platform, on which our developers can build amazing products. Our work spans many layers of the application stack – from cryptographic key management to service identity to user authentication and dynamic authorization – to achieve a modern Zero Trust architecture. We think beyond technologies and standards, to take a business-wide perspective We are seeking an engineering leader to lead our dynamic authorization effort. This team protects our customers by watching all API calls for risk indicators, triggering corrective actions when necessary. You will work with senior leaders and architects to drive strategy and execution in your area and collaborate with your peers on their areas as needed. You will model excellent communication, collaboration and execution within our team and the larger Technical Infrastructure organization. The successful candidate will be someone who can hire and retain the best, build an effective organization, work across groups to deliver broad business impact, and is not afraid to dive deep when needed. Come join us!  What You Will Do  In this role, you will:  * Help build a great team by hiring the best and actively shaping team culture.   * Drive the evolution of our platform by overseeing strategy, creating roadmaps, driving execution, and working for company-wide adoption.  * Drive alignment across key stakeholders on strategic roadmaps and deliverables.  * Partner with teams across the company to proactively identify business and technical opportunities.  * Drive execution through technical and organizational complexities, balancing strategic goals and immediate impact.   * Dive deep when necessary to lead by example and help with high priority projects.  * Contribute to the Coupang engineering community through cross-company initiatives.  * Inspire teams to raise the bar on design, development and Operational Excellence.    Basic Qualifications  * Bachelor’s degree in computer science or related technical field.   * 12+ years professional experience working in software engineering teams, or 10+ years’ experience with advanced degree.    * 5+ years’ experience managing engineers.   * Experience leading design and development of large scale distributed systems.   * Recent experience with security, IAM or related technologies.  * Experience in collaborating with cross-functional teams to define mission, vision, and roadmaps.   * Experience handling multiple competing priorities in a fast-paced environment and leading the delivery of large-scale services for complex business offerings.   Preferred Qualifications  * Masters or PhD degree in computer science or other related technical field.   * Hands-on experience building security protocols and/or systems.  * Experience in collaborating with cross-functional teams to define mission, vision, and roadmaps.   * Experience working with Infrastructure as Code, Kubernetes, gRPC and Istio.    Recruitment Process   * Application Review -> Phone Interview -> Onsite (or Virtual Onsite) Interview –> Offer  * The exact nature of the recruitment process may vary according to the specific job and may be changed due to scheduling or other circumstances.  * Interview schedules and the results will be informed to the applicant via the e-mail address submitted at the application stage.    Details to Consider   * This job posting may be closed prior to the stated end date for application if all openings are filled.  * Coupang has the right to rescind an offer of employment if a candidate is found to have submitted false information as part of the application process.  * Those eligible for employment protection (recipients of veteran’s benefits, the disabled, etc.) may receive preferential treatment for employment in accordance with applicable laws.  * Job titles and responsibilities may be subject to change depending on the candidate’s overall experience, etc. This will be communicated to the candidate at the appropriate time before the offer.  * Hiring may be restricted in case the legal qualifications required for hiring and work performance is not met.    Privacy Notice   * Your personal information will be collected and managed by Coupang as stated in the Application Privacy Notice located below. https://www.coupang.jobs/privacy-policy